Lathe.



PATENTBD AUG. 1, 1995; f

\ LATHE. APPLIOATIONILED JULY '22, 1902.

Aluminum UNITEE sTATEs ROBERT L. AMBROSE, OF TARRYTOWN, NEW YORK,ASSIGNOR TORAND PATENT OFFICE.

y DRILL'OOMPANY, OE NEW ,YORKQN Y., A CORPORATION OE NEW YORK.

K4LATI-119:.

To all whom, it may concern:

f Be it known that I, ROBERT L. AMBROsE, a

citizen'of the United States of America, residing at Tarrytown, countyof `VVestchester, State of New York, have invented certain new anduseful Improvements in Lathes, of which the following is a specicatiomreference being had to the accompanying drawings, forming a partthereof.

My invention relates to improvements inY lathes, and particularly tothat class of lathes known as screw-cuttinglathes.

v My invention consists in the provision, in connection with gearing forfeeding the lathecarriage forward positively and for automaticallywithdrawing the tool from engagement with the work at a predeterminedpoint, of certain improved automatic quick return mechanism forreturning the carriage quickly and positively to an initial position, inthe provision of certain improved means for operating the cross-feed ofthe lathe at certain periods, and in various other novel features ofconstruction and combination of parts, as will appear more fullyhereinafter.

= The main object of my invention is to cause the various movements ofthe lathe, as described, to operate automatically and successively.

My invention further consists in certain details of construction andcombination of parts, as will hereinafter be more fully described; andfurther objects of my invention will appear hereinafter. I will nowproceed to describe a lathe embodying my invention and will then pointout the novel features in claims. l

- In the drawings, Figure 1 is a front view of a lathe embodying myinvention. Fig. 2 is a view in transverse section, the plane of sectionbeing taken substantially upon the aXis of the cross-feed screw. Fig. 3is a top view of the lathe.y Fig. 4 is a detail sectional view showingthe relative arrangement ofthe longitudinal feed-screw for the carriageand the split nut carried by the carriage and adapted to engagetherewith. Fig. 5 is adetail view, on an enlarged scale, of certainparts of the carriage, cross-feed mechanism, and a shield employed inconnection therewith.

. An ordinary form of screw-cutting lathe is illustrated herein, inwhich 1 designates the bed, and2 3 the headstock and tailstock, whichSpecification of Letters Patent.

Application filed July 22.,

carry means whereby an object to be acted -upon may be supported.

2,6 designates the lathe-carriage as a whole, and 5 the longitudinalfeed-screw, adapted in its rotation to cause the carriage to movelongitudinally along the bed. The carriage carries asplit nut 6, whichwhen closed is adapted to engage the longitudinal feed screw, therebyconnecting the feed-screw with the carriage'. (See particularly detailFig. 4.) A cam 7 mounted upon a spindle 8, is also car ried by thecarriage, and when turned in the position at which it is shown in Fig. 4of the drawings will force the two portions of the split nut 6 apart andcause them to disengage the feed-screw. A pinion 9 is secured to thesame spindle 8 to which the cam is secured and meshes with asmallgear-wheel 10/upon a spindle 11, also carried by the carriage. Levers 12and 13 are mounted upon the spindles 8 and 11 and are secured to therespective pinions 9 and 10. A spring 14 tends to draw the two levers 12and 13 together. 'Ihelever l12 is preferably provided with a knob orhandle, by which it may be turned by hand to the left looking at Fig. 1or returned again to the position in which it is shown in Fig. 1. Thepinion connections will cause the levers 12 and 13 to have similarmovements upon opposite Sides of their centers, and a movement to aposition slightly past their centers in either direction will cause thespring 14 to act to continue the movement on such side of the centers tothe limit allowed. When the levers 12 and 13 are in the position shownin Fig. 1 of the drawings, the cam 7 will be with the pinion 9. Securedto move with the 'spur-gear 15 is a tripping-finger 16, and stationaryabutments 17 18 are carried by the bed and arranged in the path ofmovement of the finger 16. Upon the continued return movement of thecarriage along the bed 1- that is to say, Aupon the continued movementto the right of Fig. l-the tripping-linger 16 in the position shown inFig. 4 and the split` nut at such times out of engagement with thelfurther carries a spur-gear 15, which meshes of movement of the cam 31.

will strike the stationary abutment 17 and will partially rotate thespur-gear 15, so as to throw the levers 12 and 13 upon the oppositesides of their centers. This will cause the split nut 6 to rengage thefeed-screw 5, and the carriage 26 will be then fed forward along the bedin a direction toward the left of Fig. 1 until the tripping-finger 16strikes the stationary abutment 18, when the levers 12 and 13 and theircorrelated parts will be returned to the position in which they areshown in y Fig. 1 and the split nut 6 caused to again disengage thefeed-screw 5.

I have shown means whereby yielding pressure may be applied to returnthe carriage to its initial position when the feed-nut is disengagedfrom the feed-screw in a cylinder 19, which is in open communication atone end through the pipe 2O with a source of compressed airor the likeand a piston 21, mounted in said cylinder and connected with thecarriage 4 by means of a vconnecting-rod 22. When forced forward, thecarriage will move against the resistance of yielding pressure withinthe cylinder 19, and such pressure will move the carriage in theopposite direction when the split nut 6 is disengaged from thefeed-screw. rlhis yielding-pressure device for returning the carriage toits initial position constitutes a quick return for the carriage, whichis capable of moving it back very rapidly and much more rapidly thancould be done by reversing the lathe, as in ordinary practice, and yetwithout shock or jar either at starting or stopping.

The carriage is provided with a tool-holder 23, mounted upon a suitableslide 24,- having a transverse movement in suitable guides 25 upon thecarriage 26. A cross-feed screw 27 has a threaded engagement with adepending lug arranged upon the under side of the slide 24, and the saidcross-feed screw is suitably mounted in and carried by a block 28. Theblock 28 is also mounted to move transversely upon the carriage 26, andas a matter of construction may conveniently be arranged to slide in thesame guides 25 in which the slide 24 is mounted. The block 28 has aprojection 29l thereon, which may conveniently carry anantifrictionroller. The said antifrictionroller engages an angularearn-slot 30, arranged in a sliding cam-bar 31, mounted to slidelongitudinally in suitable ways 32 upon the carriage 26. Stationaryabutments 33 34 are arranged upon the bed 1 and in the path When thecarriage approaches the limit of its movement in either direction, thecam 31 engages either the stationary abutment 33 or 311, in accordancewith which direction the carriage is moving. A movement of the cam 31 tothe left with respect to the drawings will force the block 28 inwardlyand, by reason of the fact that the block 28 carries the cross-feedscrew 27 will move the tool-holder 23 and the tool carried thereintoward the work. A movement in the opposite direction and to theposition in which the parts are shown in Fig. 3 of the drawings willmove the transversely-movable block and tool -holder outwardly towithdraw the tool from the work.

Across-feed may be given to the tool-holder entirely independent of suchbodily transverse movement by rotating the feed-screw 27 in the ordinarymanner, as by the handle l have provided automatic means, however, bywhich a cross-feed may be given to the toolholder upon eachreciprocation of the carriage along' the bed, and hence upon eachcross-reciprocation of the tool-holder with respect to the carriage 26.Such means comprises a lever 36, loosely mounted upon the cross-feedscrew 27, a pawl 37, carried by said lever, a toothed wheel .38, securedto the said crossfeed screw 27, an operating-lever 39, pivotally mountedupon the slide-rest, and a link 40, secured to the lever 36 at theopposite end to that carrying the pawl 37 and secured at its other endto the operating-lever 39, the operating-lever 39 having at its oppositeend a connection 41 with the cam 31. hen the cam 31 is operated to movethe tool-holder and block bodily inward, the feed-screw 27 will at thesame time be given a partial rotation so as to feed the tools slightlyforward with reference to the position it held at the previous stroke. Amovement ol the cam in the opposite direction to withdraw the toolholderwill cause the pawl 37 to ride freely over one or more teeth of thewheel 38 to be in a position to again operate upon'the next stroke. Theconnection between the link l1() and the operati ngflever willpreferably be an adjustable one, so that the amount of feed given to thecross-feed screw may be varied 4as desired.

` A complete cycle of operations is then as follows: Starting with thecarriage at the extreme right of Fig. 1, with the levers 12 and 13 uponthe opposite sides of their centers to which they are shown, and thefeed-nut 6 consequently'in engagel'nent with the feed-screw 5, the cam31 in its position to the left of the figures in the drawings, and thetool and toolhold'er 23 in its inward adjustment, rotation of thedriving members of the lathe will ad- Vance the carriage Llalong the bedtoward ythe left of Fig. 1 of the drawings and against the yieldingpressure within the cylinder 19 until finally the cam 31 strikes thestationary abutment 341, and the tool-holder 23 and tool carried therebyare gradually withdrawn from the work. At about the same time thetripping-finger 16 will come into engagement with the stationaryabutment 18 and will gradually force the levers 12 and 13 over to theopposite sides of their centers until when the tool has been entirelywithdrawn from the work the feed-nut will be linally caused to disen-Elastic pressure in gage the feed-screw 5.

the cylinder 19 acting upon the piston 21 will now quickly returnthecarriage 26 along the bed until the cam 31 is engaged by thestationary abutment 33 to again move the tool and tool-holder toward thework, and simul taneously the tool will be slightly fed forward withrespect to its previous position by the cross-feed mechanism. `At aboutthe samev mined point I have provided an adjustable shield 42,adjustably secured to the toothed Wheel 38 and which after the toothedwheel 38 and the cross-feed screw27 have been rotated a predetermineddistance will pass in beneath the pawl 37 and prevent it engaging theteeth of the said wheel 38. By this means no further inward feed of thetool will be caused by the automatic action and continued reciprocationof the parts; but such movement will merely be free movements.

I do not desire to be limited to the precise details of4 construction orcombination of parts herein shown and described, as the same mayobviously be varied withinY wide limits without departing from thespirit and scope dilferent construction.

1. In a lathe, the combination With a bed, and means for supporting workto be acted upon, of a longitudinally-movable carriage, longitudinalfeeding mechanism therefor comprising gearing arranged to feed thecarriage positively, means for releasing the carriage therefromautomatically, and automatic return mechanism for the carriagecomprising a cylinder and piston, the one `secured to a fixed supportand the other connected to the carriage, and means for supplying Huidunder pressure to said cylinder.

2. In a lathe, the combination with a bed, and a leadscrew, of acarriage, a split nut carried thereby adapted to grasp` said screw, andmeans for contracting or expanding said nut, comprising anoperating-arm, another arm geared thereto, and arranged to point in adi, ametrically opposite direction when in an intermediate position, aspring connecting said arms and means for operating said armsautomatically, to throw them upon opposite sides of said diametricallyopposite intermediate position.

3. In a lathe, the combination with a bed, and a carriage longitudinallymovable thereon, of cross-feed mechanism for said carriage, aratchet-wheel and pawl for operating the same, means operated by themovement of the carriage for operating said pawl, and an adjustableguard for the ratchet-wheel, and carried thereby.

4. In a lathe, the combination with a bed i having stationary abutments,and a carriage longitudinally movable along said bed, of a tool-holdertransversely movable upon said carriage, a longitudinally-movablecam-slide upon said carriage arranged to move the toolholdertransversely in opposite directions, said cam-slide arranged to be movedlongitudinally with respect to said carriage by said stationaryabutments, a cross-feed mechanism for said tool-holder including aratchet mechanism for operating the same, and connections between saidratchet mechanism and said cam-slide, for operating the said ratchetmechanism.

5. In a lathe, the combination with a bed having stationary abu tments,a carriage longitudinally movable along said bed, and a toolholdertransversely movable upon said carriage, of a cam-slide longitudinallymovable upon said carriage, and arranged in its longitudinal movementsto impart transverse move ments to the tool-holder, said cam-slide movedlongitudinally with respect to said carriage by engagement with saidstationary abutments in -the longitudinal movement of said carriage,

cross-feed mechanism for said tool-holder comprising a ratchetmechanism, an operating-lef ROBERT L. AMBRosE.

Witnesses:

A. W. PATTERSON, J r., N. J. BARNUM.'

